Air pumps do two beneficial things, aeration and mixing. I've been using 1 of these for 2 airstones in 2.5 gallons of reservoir fluid, as an experiment. I'll be testing some new, bigger reservoirs with 8 gallons of fluid, and I'll be using 2 of these dual pumps to power 4 small air stones. I'm more worried about enough mixing than I am about enough aeration. I've also used a General Hydroponics Ecogrower system that had top feed with no air stone, and the aeration from the top feed is good enough. I tested 2 of these side by side, one with airstone, the other without, and saw no difference.
Currently running 2 of those ^ but the model with 8 outlets, to 2 stones in each 5 gallon bucket. Works great, just wondering if too much air can be an issue
This is what I use. I added a buffer (the can) to cut down on the noise. This really helps as the resistance keeps the piston from slapping against the end stop. Like a small air compressor setup, which is really what it is.
You really don't need more pics. Some people use a liter bottle. Just put a "go-insa" and a "go-outsa" length of tubing through the cap and seal it. So the pump fills the bottle through the go-insa line and then empties through the go-outsa line which has a valve on the outlet. This will really cut down the noise.
Some people dont learn by other peoples explanations alone,call me stupid but I'd appreciate another picture to understand the system. If you dont want to, I understand.
These are a fantastic pump without the need to make up dodgy can muffler rigs. Lot more cost efficient than compressor type pumps & a lot lot quieter. - The Hailea ACO-9720 has an aeration output of 1800L/Hour whilst making less than 40Db of noise and drawing only 20W of power. These Pumps are very very good value & extremely well made, they're a commercial aquarium pump.